I have two servers with battery backed power supply (USV). So it is unlikely, that both will crash at the same time.
Will synchronous replication work with fsync=off? That means we will commit to system cache, but not to disk. Data will not survive a system crash but the second system should still be consistent.
Or: will it work with master: fsync=off and slave(s): fsync=on? In this case master is free for read-queries and slave has time to do all the heavy writing. Data on master will not survive a crash but can be restored from slave.
